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I don't know if this is the total truth, but it's interesting.

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Type: Discussion • Score: 8 • Views: 2,583 • Replies: 29
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[+4] - tsarstepan - 08/12/2019[quote="farmerman"] You say that visibility i just that of humans, I disagree. [/quote] It's nice that you... ((sigh)) disagree. But according to the NASA page (sourced above which...
[+3] - tsarstepan - 08/12/2019[quote="Leadfoot"] No, we see 100% of the visible (to humans) light spectrum. The OP link is a meaningless statement as written. [/quote] This is technically correct. [quote]As...
[+3] - Leadfoot - 08/12/2019Context is everything and 'visible' wasnâ��t defined other than in the context of 'human'. Even if you want to use your definition, Iâ��d question the 1% figure. But the real...
[+3] - tsarstepan - 08/12/2019[quote="Leadfoot"] Context is everything and 'visible' wasnâ��t defined other than in the context of 'human'. Even if you want to use your definition, Iâ��d question the 1%...

@edgarblythe,

it was often a big deal for hunters that were out shooting birds. They see in the ultraviolet and their world is one of bright eyeball returns . SOO, whenever we went pheasant and partridge hunting we would try to remove all the traces of detergents that mom would use to wash out hunting gear. All detergents are basically loaed with Titanium dioxide salts which glow bright bluish (to us after shining a uV light on em)> A bird can pick you out like a lightbulb in a dark room if your mom TIDEwashed your garb. My wife wont touch my hunting garb she makes me take em to a laundromat along with the cat blankets.

n a bar will try.

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@edgarblythe,

No, we see 100% of the visible (to humans) light spectrum.

The OP link is a meaningless statement as written.

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@Leadfoot,

no it isnt. "visibility" is merely the spectrum that can be detected by something(usually living). We are blind to that %age because we dont have the quadripartite set of cones (there is a hexapartite too but that i only held by a few deep sea fishes).

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@farmerman,

Thanks. I post this stuff on the childlike faith that somebody in the know will help explain it. Usually I am rewarded.

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@Leadfoot,

Leadfoot wrote:

No, we see 100% of the visible (to humans) light spectrum.

The OP link is a meaningless statement as written.

This is technically correct.

Quote:

As you can see, the visible portion makes up an incredibly small fraction of the total electromagnetic spectrum. Less than 1% of all light that reaches us is in the visible spectrum. By most estimates it comes out to about.0035% of the entire electromagnetic spectrum.

Therefore what humans see is 100% on the visible spectrum.

A more authentic source than above.

The statement made by Edgar is written erroneously. It's also a pretty lame platitude.

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@edgarblythe,

I think we are but part of the ecosystem, not THE reason for it.

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@farmerman,

Context is everything and 'visible' wasn’t defined other than in the context of 'human'. Even if you want to use your definition, I’d question the 1% figure.

But the real implication of the OP is that we are terribly limited in our perception of 'reality'. That POV has no understanding of system optimization. Selectivity can be a valuable property, especially with a wet computer working at sub gigahertz speeds. Just imagine if we saw into the microwave region, there would be blinding beacons all over the place.

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@Leadfoot,

Leadfoot wrote:

Context is everything and 'visible' wasn’t defined other than in the context of 'human'. Even if you want to use your definition, I’d question the 1% figure.

According to my two sources, the 1% figure is correct in terms of light that humans cannot see through the naked eye. It's erroneous labeling of light beyond the 1% as visible? That's the error. One of the sources is straight from the official NASA website.

1 Reply

@tsarstepan,

I’ll go along with that. It was just a poorly posed factoid.

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@Leadfoot,

Quote:

Quote:
But the real implication of the OP is that we are terribly limited in our perception of 'reality'. That POV has no understanding of system optimization. Selectivity can be a valuable property, especially with a wet computer working at sub gigahertz speeds. Just imagine if we saw into the microwave region, there would be blinding beacons all over the place.

whatever that means, sounds great. Visibility as I read it was NOT limited to human perception.
You say that visibility i just that of humans, I disagree. We call the sensing of e mag radiation "visibility". I read it as about all e mag perceiving life, not jjust humans. Otherwise, wed probably have our applied research be limited by these "human centered" constraints.
How else did we wind up learning about "color visibility" as applied to non-humans?

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@farmerman,

farmerman wrote:

You say that visibility i just that of humans, I disagree.

It's nice that you... ((sigh)) disagree. But according to the NASA page (sourced above which you CLEARLY did not reference) ... what scientifically is coined
VISIBLE LIGHT is the range of spectrum that humans can see (barring physical disability that an individual might have).

You can ... ((sigh)) disagree ALL you like. That doesn't make you right. Makes you pretty stubborn. The term visible light is a human centered term based on the parameters of the ideal sight of an ideal human being (make of it what you will).

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@tsarstepan,

NASA doesnt speak for biologists. A buddy of mine who teaches optical physics has defined the spectrum , not by wavelength but by species who "perceive any wavelength".

Science always disagrees with itself , I love to perceive the many sides of imprecise things.

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@tsarstepan,

Quote:

It's nice that you... ((sigh)) disagree

I thank you, Its nice that you say its nice

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@farmerman,

farmerman wrote:

no it isnt. "visibility" is merely the spectrum that can be detected by something(usually living). We are blind to that %age because we dont have the quadripartite set of cones (there is a hexapartite too but that i only held by a few deep sea fishes).

Lets assume that your definition is correct... I still think the 1% figure is bullshit.

Human vision extends (in general) from 740 to 380 nm on the electromagnetic spectrum (I am using wavelengths, a shorter wavelength corresponds to a higher frequency). I just looked up bee vision (because I remember hearing that bees see ultraviolet). It seems they can see down to 300nm (but they can't see the higher wavelengths that humans can see).

Our atmosphere filters out the shorter wavelengths. There is no reason that any animal would evolve to see light that doesn't exist in their environment. And below "visible" light are radio waves.

I don't see how this 1% figure makes any sense... what are the other 99%.

I am pretty sure this is pure bullshit. It is another version of the myth that we only use 1% of our brains.

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I should also point out that that humans can build machines from radio telescopes to gamma ray detectors.

Humans can see quite a bit more of the spectrum than any other life form on Earth.

1 Reply

@edgarblythe,

In a similar vein I heard that bats are really noisy, and if their screeches weren't too high pitched for us to hear they'd keep us up all night.

1 Reply

@izzythepush,

Might be right.

When I was younger and TVs had CRTs, the horizontal deflection frequency noise was so loud it gave me headaches, had to quit my job at a TV repair shop. I swear I could hear bats too.

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@Leadfoot,

I had to look it up, I take it you mean a cathode ray tube, not the Canal and River Trust, although I believe my telly did have one of those.

1 Reply

@Leadfoot,

Leadfoot wrote:

I swear I could hear bats too.

Are you Batman?

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